I have a couple of questions for you guys that know what you are doing

First, my blms. They are about 125 and 122 or in that area. That seems to be as high as I can get them before they go higher than 128 at WOT. I was told it was better to be on the low side of 128 when I go into WOT so the computer won't blindly add fuel. Is this right?

Second, timing. I have played with the tables a little but it is a little more complicated than setting the total timing on my Mustang. I have just been multiplying the whole table by whatever I want the timing to be. Like I have multiplied it by 10%. I did show a 3 hp gain on the dyno but when I scaled it by 15%, no change after the 3hp happened. No knock retard was recorded at any time. Do you guys add timing here and there? Is there a way I can try to maximize torque and hp by varying the amount of advancement?

Last for now, AFR. I made the dyno pulls with a wide band so I know the AFR. What is generally the lag(in rpms) at which it takes the reading as to when it actually produced the gas? I heard it was around 400 rpms. Like I said, I know the AFR. What is the target I should shoot for for maximum hp and torque. Does it need to change? Like, will it make more torque at a leaner AFR and more hp at a richer AFR?

Anyway, I hope you made it this far. Any suggestions will be greatly appreciated.

Thanks, Mike Dawson.

 

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If you're going to tune the car on a dyno I think it would be easier just to lock the cell 15 blms at wot.

Are you talking about multiplying the whole table by 3%, or just the 90-100map stuff?
That should be the stuff you want to change for wot.
IMHO, you should try to bring full advance in as quick as you can. That should help build low end torque. But remember that the computer does add timing above what is shown in the tables. Check a post from the last week or so and you'll see where I was talking about it before.
I would set it up so that you can bring the timing in quickly and then hold 32 degrees the whole time. Then bump it up to 34 and try it. Then try 36. If the car is still picking up hp/mph then try 38. If you stop picking up hp/mph then stop or maybe go back to the last amount you tried. It's something you'll have to experiment with to see what each car runs best with.

Lag? I think I've been told before it is a couple hundred rpm, maybe 400, but it doesn't matter. You should be shooting for a constant a/f ratio. Probably around 13:1...but again, each car is different. It might like 12.5:1...maybe 12:1. But I would go much leaner than 13:1 at all.

 

[QUOTE]Originally posted by Dan K
[B]
Are you talking about multiplying the whole table by 3%, or just the 90-100map stuff?
That should be the stuff you want to change for wot.
IMHO, you should try to bring full advance in as quick as you can. That should help build low end torque. But remember that the computer does add timing above what is shown in the tables. Check a post from the last week or so and you'll see where I was talking about it before.
I would set it up so that you can bring the timing in quickly and then hold 32 degrees the whole time. Then bump it up to 34 and try it. Then try 36. If the car is still picking up hp/mph then try 38. If you stop picking up hp/mph then stop or maybe go back to the last amount you tried. It's something you'll have to experiment with to see what each car runs best with.

I have been multiplying the whole table by 10 percent. I haven't tried just the wot values. Do you mean add more timing sooner? Like as soon as you go WOT?

Thanks for the help. I will try it as soon as I get my 3-4 fork fixed.

 

Not sure what program you're using, but in TunerCat there are 2 tables... Main Spark Advance and Extended Spark Advance. These tables, as well as others, affect your total timing. So if you bump those tables up to 32, your total timing at a particular time all said and done, might end up being 30 or 38, dependng on coolant temps, retard, etc.

Anyways, those 2 tables I mentioned are RPM vs. MAP. The MAP is load, 100 being WOT. I also edited those tables, but from about 3000 RPMs up, and only the 90, 95, and 100 MAP sections.

If you just edit the whole table, then you're also changing part throttle timing... not a bad idea I guess, but tougher to figure out if you're doing any good.

 

Well I have been modifying both tables, just been referring to them as one. I use Tunercat.

I think I will put the timing back stock and then just modify it in the 90-100 map range.

My coolant never goes past 195 and I never get any retard. My iat stays about 5-10degrees hotter than ambient.

I would tune it at the dyno again but I am about to put a supercharger on it and the timing won't do any good. Until then though, I wanted to see some gains at the track. How much hp do you think I could see with just the timing increased?